By Greg Stutchbury
MELBOURNE (Reuters) - Top seed Novak Djokovic and champion Stan Wawrinka set up 'The Djoker v The Man 3.0' at Melbourne Park after impressive quarter-final victories on Wednesday, while an ill Serena Williams moved a step closer to her 19th grand slam title.
The American, however, will first have to overcome the pure hitting of Madison Keys after the 19-year-old ended the fairytale run of Serena's older sister Venus, despite suffering from a thigh injury that hampered her movement.
With many suggesting prior to the tournament it could signify an epochal shift in both games, the teenager represents the up and comers in the semi-finals after Djokovic and Wawrinka crushed the last hopes of 'Generation Next' in the men's draw.
Djokovic, seeking to become the second man to win a fifth Australian Open title, beat Canada's Milos Raonic 7-6(5) 6-4 6-2 in the late match on Rod Laver Arena, hours after Wawrinka had easily dispatched fifth seed Kei Nishikori 6-3 6-4 7-6(6).
"Definitely expecting a marathon like the last couple of years. I'm sure that both of us will give our best to perform our best tennis," Djokovic said in a courtside interview.
"We always ask for the best of each other."
It will be the third successive year Djokovic and Wawrinka have met at the Australian Open, with the man winning those epic clashes ultimately going on to clinch the title.
As defending champion in 2013, Djokovic prevailed 12-10 in the fifth set in their fourth round clash.
Last year, Wawrinka won the fifth set 9-7 in their quarter-final, indicating fans on Friday should be set for another epic encounter.
"You know when you play Novak, especially in semi-final in a grand slam, you have to play your best game," Wawrinka said.
"You have to play your best tennis if you want to push him. So far I'm playing great. I'm confident with my game."
PARTY POOPER
American teenager Keys proved to be the ultimate party pooper with her victory over Venus while at the same time indicating the mantle of American women's tennis should be in safe hands when it is moved on from the two sisters.
Serena and Venus had been hoping to provide fans with the first all-Williams sisters clash at a grand slam since the 2009 Wimbledon final in the semi-finals.
Keys, who was inspired at four years old to take up the game after seeing Venus play at Wimbledon, refused to succumb to sentimentality and demonstrated the ball striking and power hitting, which had destroyed players of the calibre of double Wimbledon champion Petra Kvitova, in a 29-minute first set.
An adductor injury that forced her out of the Wimbledon third round last year, just days after she had stormed to the Eastbourne title, however, flared up again in the second set, which brought back some desperate memories.
"It was definitely a flashback to Wimbledon for me," Keys said of the injury that forced her to take an injury break while trailing 4-1 in the second set.
"It was quite an overwhelming moment and scary ... and I had the nightmare of 'I don't want this to happen again'."
Keys, now coached by former number one Lindsay Davenport, however, showed her maturity and mental toughness once she settled to overpower Venus and battle through the injury to advance to her first grand slam semi-final.
"It's definitely an amazing moment," she added. "I'm enjoying those moments for little bits of time and then refocusing and thinking about the next round."
Keys' chances of making the final have improved with the world number one battling the effects of a cold after a virus hit several players at the tournament.
"I've been sick the past few days," a hoarse-sounding Serena told reporters after her 6-2 6-2 destruction of last year's finalist Dominika Cibulkova.
"It's just getting worse and worse. I heard it's a virus going around with a lot of the players.
"I think I caught it."